Mechanical structure and force loop

Frame and primary structure

Welded steel box-section construction
Two rectangular frames:
- lower frame
- upper frame
Frames connected by four vertical steel legs
Box sections sized for stiffness via geometry, not mass
Welding limited to areas where deformation is acceptable

Frame bracing

Steel tension members used for frame bracing
Implementation:
- threaded steel rods
- or steel tubes with internal threads
Bracing applied on both diagonals
Members preloaded to pull frame into square
Bracing is:
- non-moving
- serviceable
- not part of damping strategy

X gantry structure

Two parallel horizontal box-section beams
Beams span the upper frame
Beams support:
- spindle tower
- X-axis motion
Beams connected to linear bearing blocks on upper frame rails
Beam spacing sized to accommodate:
- spindle plate
- Z-axis rails
- spindle housing

Spindle tower

Constructed from steel plates (approx. 10 mm thickness)
Plates bolted together (not welded)
Alignment procedure:
- tower aligned perpendicular to table
- fasteners torqued
- holes drilled and reamed
- dowel pins inserted to fix alignment
Tower rigidly connects spindle plate to X gantry beams

Force loop definition

Explicit force path during cutting:
- tool
- spindle
- spindle housing
- spindle mounting plate
- spindle tower
- X gantry beams
- frame
Structural elements outside this loop are not considered load-bearing

Table and Y-axis support

Steel table plate (approx. 10-15 mm thickness)
Four linear bearing blocks mounted under table
Bearing blocks positioned near table corners
Primary loading of bearing blocks in Z direction
Two Y-axis rail support beams:
- bolted to lower frame
- parallel to frame sides
Rail support beams are removable and alignable

Optional table stiffening

Shallow steel ribs or profiles may be added under table plate
Attachment method:
- adhesive bonding
- bolting
No welding to table plate